memtester is a user-space utility for testing the
memory subsystem in a computer to determine if it
is faulty. It does a good job of finding
intermittent faults and non-deterministic faults.
It has many tests to help catch borderline memory. memtester should
compile and run on any 32- or 64-bit Unix or
Unix-like system.

ProcMeter3 is a program for monitoring the system status and other information and displaying it in a series of graphs or as text. Most of the information comes from the /proc filesystem (cpu usage, load average , processes information, memory usage, network traffic, interrupts etc.). Other information is available for other sources (date, time, email status, log file length, disk status etc.). The program is modular and highly configurable.

The main purpose of LoFiMo is, as the name states, to monitor log files. It does this in real time, i.e. shows the contents of log files as they are changing. The user can connect to LoFiMo with a Web browser or use the console for plain text output. When using a Web browser, the output can be formatted with cascading stylesheets, which the user can define. Thus, it is possible to highlight certain log entries with different colors and fonts. It is also possible to play sounds or execute commands (send an email, play sound with a custom player, etc.) when a log entry matches a filter.
LoFiMo can parse Apache style log files and syslog style log files. Among others, there are filters that can parse iptables logs and merge multiple log lines of Postfix into a single one.

TCP Re-engineering Tool monitors and analyzes data transmitted between a client and a server via a TCP connection. It focuses on the data stream (software layer), not on the lower level transmission protocol (as packet sniffers do).

SystemRescueCd is a Linux system available from a bootable CDROM
that provides an easy way to perform administrative tasks on your
computer, such as creating and editing the partitions of the hard disk
or backing up data. It contains a lot of system utilities (such as
parted, partimage, and fstools), and basic programs (such as editors,
midnight commander, and network tools). It also includes GParted, a
Partition Magic clone that makes editing partitions easy with its
graphical user interface. This CDROM aims to be very easy to use and
accessible to everybody, and it also provides advanced personalization
features.

INSERT (the Inside Security Rescue Toolkit) aims
to be a multi-functional, multi-purpose disaster
recovery and network analysis system. It boots
from a credit card-sized CD-ROM and is basically a
stripped-down version of Knoppix. It features good
hardware detection, fluxbox, emelfm, links-hacked,
ssh, tcpdump, nmap, chntpwd, and much more. It
provides full read-write support for NTFS
partitions (using ntfs-3g), and the ClamAV virus
scanner (including a fairly recent signature
database and a GUI). It provides partition
handling with gParted and also has a network boot
facility.

Ultimate Boot CD is a collection of Freeware and Free Software tools for PC diagnostics and maintenance. Included are tools for BIOS editing, CPU and memory testing, boot management, data recovery, peripheral and system inventory, and hard drive partitioning, cloning, wiping, diagnostics, and low-level editing. All tools boot and run from the CD.

Open HPI is an open source project created to provide an open implementation of the SA Forum's Hardware Platform Interface (HPI). It provides a universal interface for Platform Management, including hardware sensor monitoring and control.